Concrete batching plants must adhere to strict statutory requirements regarding the control of environmental conditions. One area that requires particular attention is the delivery, storage, weigh and transfer of aggregate, such as sand and gravel.
Aggregate is typically stored in storage bins. A loader, such as a front end loader, is used to periodically transport aggregate from the bin to an overhead storage hopper. A weigh hopper is generally situated directly below the storage hopper. A weighed amount of aggregate is gravity fed from the storage hopper into the weigh hopper and then transferred to a batching area.
The aggregate storage bins are situated at ground level, and are enclosed on three sides to shield the aggregate from wind. However, the top and at least one side of the bunker is open, exposing the aggregate to wind. Wind can disperse fine particulate matter, polluting both the plant and surrounding area. The loaders used to transport the aggregate are also open and further fine particulate matter is dispersed during transport.
One attempt to alleviate the dispersement of the aggregate is to locate the storage bin underground. However, loaders are still required to transport the aggregate from the bin to the overhead storage hopper.
The aggregate delivery, storage, weigh and transfer of aggregate in current concrete batching plants is complex, and installation and maintenance costs are high. The storage hoppers must be constantly replenished, with use of the loaders creating traffic hazards to plant employees. To allow manoeuvring of the loaders between the storage bin and the storage hopper, a significant amount of space is required within the plant for the aggregate delivery, storage, weigh and transfer. Common in all batching plants are the problems associated with dust and noise emissions.
It would be desirable to provide an aggregate delivery, storage, weigh and transfer system that alleviates or overcomes one or more problems associated with known systems.